Wipers have been created to satisfy both the needs of commercial (industrial) or individual consumer (domestic) applications. Domestic and industrial wipers are often used to quickly absorb both polar liquids (e.g., water and alcohols) and nonpolar liquids (e.g., oil). The wipers must have a sufficient absorption capacity to hold the liquid within the wiper structure until it is desired to remove the liquid by pressure, e.g., wringing. In addition, the wipers must also possess good physical strength and abrasion resistance to withstand the tearing, stretching and abrading forces often applied during use. Moreover, the wipers should also be soft to the touch. In particular, industrial wipers which are regularly used to clean oil, grease and grime, are often squeezed into narrow crevices of machinery. Therefore, such wipers should be easily conformable in and around small openings.
In the past, nonwoven fabrics which are typically hydrophobic, such as meltblown nonwoven webs, have been widely used as wipers. Meltblown nonwoven webs possess an interfiber capillary structure that is suitable for absorbing and retaining liquid. However, meltblown nonwoven fibrous webs sometimes lack the requisite physical properties for use as a heavy-duty wiper, e.g., tear strength and abrasion resistance. Consequently, meltblown nonwoven webs are typically laminated to a support layer, e.g., a spunbond nonwoven web, which may not be desirable for use on abrasive or rough surfaces.
Spunbond and staple fiber nonwoven webs, which contain thicker and stronger fibers than meltblown nonwoven webs and typically are point bonded with heat and pressure, can provide good physical properties, including tear strength and abrasion resistance. However, spunbond and staple fiber nonwoven webs sometimes lack fine interfiber capillary structures that enhance the adsorption characteristics of the wiper. Furthermore, spunbond and staple fiber nonwoven webs often contain bond points that may inhibit the flow or transfer of liquid within the nonwoven webs. As such, a need remains for a fabric that exhibits the requisite strength and good oil and grease absorption properties for use in a wide variety of wiper applications.
Further, since certain nonwoven manufacturing processes often lead to the production of fairly rigid nonwoven materials, there is a need for wipers which are softer and more gentle to the touch, and further that are conformable so as to allow such wipers to be used in small openings and around a variety of shaped objects and inside crevices, where oil and grease may accumulate. It is to such needs that the current invention is directed.